Integrated IR receiver in side-lit panels

Abstract

The invention provides a lighting device (100) comprising a plurality of light sources (10), a light guide plate (20), a rim (30), and an IR sensor (40), wherein: (i) the light sources (10) are configured to provide light source light (11), and wherein the light sources (10) are configured in an edge-lighting configuration with the light guide plate (20); (ii) the light guide plate (20) comprises a circumferential edge (22) of which at least part is configured as light incoupling face for the light source light (11), and a first face (21) of which at least part is configured as light outcoupling face; (iii) the rim (30) comprises the plurality of light sources (10) and the IR sensor (40); and (iv) the IR sensor (40) is configured to sense IR radiation (41) via the light guide plate (20).

The invention claimed is: 
     
       1. A lighting device comprising a plurality of light sources, a light guide plate, a rim, and an IR sensor, wherein:
 the light sources are configured to provide light source light, and wherein the light sources are configured in an edge-lighting configuration with the light guide plate; 
 the light guide plate comprises (i) a circumferential edge of which at least part is configured as light incoupling face for the light source light, and (ii) a first face of which at least part is configured as light outcoupling face; 
 a reflector, wherein the reflector is configured to reflect back into the light guide plate light that escapes from the light guide plate via a second face of the light guide plate opposite the first face, said reflector being arranged at a distance (d 1 ) from the second face; 
 the rim comprises the plurality of light sources and the IR sensor; 
 at least part of the circumferential edge is configured as an irradiation outcoupling face; and, 
 the IR sensor is configured to sense IR radiation via the light guide plate. 
 
     
     
       2. The lighting device according to  claim 1 , wherein the IR radiation comprises near-infrared radiation. 
     
     
       3. The lighting device according to  claim 1 , wherein the light sources comprise solid state light sources. 
     
     
       4. The lighting device according to  claim 1 , wherein the light sources comprise light emitting diodes (LED's). 
     
     
       5. The lighting device according to  claim 1 , further comprising the plurality of light sources and a control unit functionally coupled to the IR sensor for receiving an IR signal and,
 wherein the control unit is configured to control the light source light based at least in part on said IR signal. 
 
     
     
       6. The lighting device according to  claim 1 , wherein said distance (d 1 ) is in the range of 0.7 μm to 10 mm, preferably in a range of 1.0 μm to 1 mm. 
     
     
       7. The lighting device according to  claim 1 , wherein said distance (d 1 ) from a gap, said gap being filled with air or MgF2. 
     
     
       8. The lighting device according to  claim 1 , further comprising a light transmissive optical element arranged over at least part of the first face, wherein the light transmissive optical element comprises one or more of a diffusor, a color filter, or a micro lens optics plate. 
     
     
       9. The lighting device according to  claim 1 , wherein the light guide plate comprises a rectangular shape. 
     
     
       10. The lighting device according to  claim 1 , wherein a first subset of the plurality of light sources and a second subset of the plurality of light sources are arranged at opposite parts of the circumferential edge of the light guide plate. 
     
     
       11. The lighting device according to  claim 1 , wherein at least a subset of the plurality of light sources is connected to a printed circuit board and the IR sensor is connected to the same printed circuit board. 
     
     
       12. A lighting system comprising a lighting device according to  claim 1  and a control system. 
     
     
       13. The lighting system according to  claim 12 , further comprising a user interface device functionally coupled to the control system. 
     
     
       14. The lighting system according to  claim 12 , wherein the lighting system comprises an IR transmitter configured to transmit an IR signal to be sensed by the IR sensor of the lighting device. 
     
     
       15. The lighting system according to  claim 12 , comprising a plurality of lighting devices.